#include<iostream>
#include<set>
using namespace std;
int main()
{
	typedef set<int>::iterator IT;
	int a[5] = {3,4,6,1,2};
	set<int>st(a,a+5);
	pair<IT,bool>result;
	result = st.insert(5);
	if(result.second)
	cout<< * result.first<<" inserted"<<endl;
	if(st.insert(5).second)
	cout<< * result.first<<endl;
	else
	cout<< * result.first<<" already exists"<<endl;
	pair<IT,IT>bounds = st.equal_range(4);
	cout<< * bounds.first<<","<< * bounds.second ;
	return 0;
}